Ketone bodies are produced from acetyl-CoA, mainly in the mitochondrial matrix of liver cells when carbohydrates are so scarce that energy must be obtained from the breakdown of fatty acids. Ketones are then transported from the liver to other tissues, where acetoacetate and β-hydroxybutyrate can be reconverted to acetyl-CoA to produce energy. The presence of ketones in the blood is known as ketosis. Nutritional ketosis is a result of a diet with 60-70% of energy needs coming from fat, 25-30% from protein, and 5-10% coming from carbohydrates. Beta-hydroxybutyrate (BHB), the main ingredient in Keto Metabolic™, is one of three endogenously produced ketone bodies, but it can also be taken orally as an exogenous ketone supplement. When ketones are abundant in the blood, such as during caloric restriction or a ketogenic diet, the brain can obtain up to 60% of its energy from their oxidation. It has been shown in animals that ketone bodies can also replace glucose as a cellular signal in the central nervous system. Ketones cross the blood-brain barrier and have been shown to be neuroprotective, promoting oxidative defense, enhancing mitochondrial respiration and cerebral blood flow.